We claim the ornamental design for a user interface unit for engine and/or generator, as shown and described.
FIG. 1 is a perspective view from the front, top, and left side of a user interface unit for engine and/or generator in accordance with a first variant of said design;
FIG. 2 is a perspective view from the rear, bottom, and right side of the user interface unit for engine and/or generator of FIG. 1;
FIG. 3 is a left side view of the user interface unit for engine and/or generator of FIG. 1;
FIG. 4 is a front view of the user interface unit for engine and/or generator of FIG. 1;
FIG. 5 is a right side view of the user interface unit for engine and/or generator of FIG. 1;
FIG. 6 is a rear view of the user interface unit for engine and/or generator of FIG. 1;
FIG. 7 is a top view of the user interface unit for engine and/or generator of FIG. 1; and,
FIG. 8 is a bottom view of the user interface unit for engine and/or generator of FIG. 1.
The broken lines in the drawings depict portions of the user interface that form no part of the claimed design.